Effect of time, temperature and solvent on the stability of T-2 toxin, HT-2 toxin, deoxynivalenol and nivalenol calibrants

The influence of solvent, storage time and temperature on the stability of the trichothecene mycotoxins T-2 toxin (T-2), HT-2 toxin (HT-2), deoxynival enol (DON) and nivalenol (NIV) was investigated. Toxins in acetonitrile, et hyl acetate or as thin film were stored in sealed glass ampoules at -18, 4, 25 and 40 degreesC for up to 24 months. Samples were analysed by HPLC with UV detection. The results show that acetonitrile was the preferred solvent and no significant (t(0.95)-test) decomposition occurred for any of the fo ur trichothecenes when stored for 24 months at 25 degreesC or 3 months at 4 0 degreesC. T-2 and HT-2 in ethyl acetate or as thin film were also stable under the same conditions. DON and NIV in ethyl acetate or as thin film wer e stable for up to 24 months at-18 degreesC, but a significant decompositio n of DON and NIV in ethyl acetate was observed for both toxins after 24 mon ths of storage at 4 degreesC and after 12 months at 25 degreesC. When store d as thin film, a significant trend of decomposition of DON occurred after 24 months of storage at 4 degreesC and after 6 months of storage at 25 degr eesC. A significant decrease of NIV stored as thin film was observed after 9 months at 25 degreesC. In conclusion, acetonitrile was the most suitable solvent for long-term storage of T-2, HT-2, DON and NIV.